Aim: This study aimed to detect Brucella organisms in Egyptian raw milk using cultural and molecular techniques.
Methods: Two hundred bulk milk samples were collected from 2 cities at El-Gharbia and Kafer El-Sheikh Governorates during the summer and winter seasons. All samples were examined by the traditional cultural method and real-time polymerase chain reaction (qRT-PCR). All positive isolates were identified by biochemical tests and serotyping using monospecific antisera also examined by multiplex PCR primers for more identification.
Results: Samples collected in summer seasons from the two cities showed no colonies characteristic to Brucella organisms while in winter season five samples showed positive characteristic features of Brucella organisms after culturing on Brucella specific media. Using qRT-PCR, 43 samples (13 in summer and 30 in winter) were positive for Brucella organisms. All positive RT-PCR samples and isolated strains were examined for the detection of the virulence genes Ure, bvfA and virB using conventional PCR. Ure, bvfA and virB were detected in 88%, 79% and 74% of milk samples and 100%, 80% 100% of isolates, respectively.
Conclusion: These results suggested that the use of the specific PCR assay is a rapid, reliable, and accurate technique in comparison to traditional methods for the detection of Brucella species in milk samples.